Republican leaders have introduced sweeping changes to their contentious plan to repeal and replace the Affordable Care Act (ACA) in an attempt to sway wary conservatives and moderates. But a coalition of House hardliners said they were not persuaded.

The House Republican leadership is racing to shore up support for the proposed healthcare overhaul before a planned vote on Thursday. Donald Trump will meet with Republicans on Capitol Hill on Tuesday morning to rally party members.

The revision to the bill, known as the American Health Care Act, is intended to placate conservatives with changes to Medicaid as well as the moderates who are concerned the original proposal would hurt older patients.

A week ago an analysis by the Congressional Budget Office forecast that 24 million people would lose their healthcare coverage by 2026 under the original plan. It also found that premiums would rise in the short term but then drop lower than they would if the ACA remained in place over the next decade. However, under the Republican proposal, older and low-income Americans would face significant increases in cost.

The amendment is the result of two weeks of aggressive negotiations between administration officials, the Republican leadership and a bloc of conservative lawmakers. It included numerous meetings at the White House, on Capitol Hill and a weekend summit at Trump’s Mar-a-Lago estate.

The House speaker, Paul Ryan, said in a statement on Monday night: “With this amendment we accelerate tax relief, give states additional options to spend healthcare dollars how they choose, strengthen what were already substantial pro-life protections and ensure there are necessary resources to help older Americans and the disabled.”

Key changes to the bill include allowing states to impose work requirements on Medicaid recipients; granting a lump sum of federal Medicaid funding to states to do with as they wish; and immediately prohibiting any additional states from expanding the Medicaid program. The initial proposal allowed states to expand Medicaid until January 2020.

The revision also hastens the repeal of ACA tax provisions – such as increases on higher earners and the medical industry, among others – from 2018 to 2017, a win for conservatives who want to see them removed as quickly possible.

Another change would provide additional tax credits to help older Americans, who would see dramatic increases in their premiums under the current proposal, but are letting the Senate draft the language for the provision.

The proposal also included a provision that applied only to New York – an attempt to lure the comparatively moderate GOP delegation from the Empire State. The measure would shift Medicaid costs from individual counties to state taxpayers in an effort to help the constituencies of several Republicans from upstate New York.

Even before the amendments were formally posted, the hard-right House Freedom Caucus said the changes still did not do enough to repeal the current healthcare law, known informally as Obamacare. North Carolina representative Mark Meadows, the caucus chairman, said he had been told that the negotiations were finished and the amendments offered on Monday would be the last.

“I’m confident that we still have enough concerns that a vote of 216 votes in the House would not happen today,” Meadows told reporters after a Monday evening caucus meeting, referring to the minimum number of votes the bill will need to pass the House.

Senators Ted Cruz of Texas, Mike Lee of Utah, and Rand Paul of Kentucky, joined the Freedom Caucus meeting on Monday to rally members in opposition to the bill.

Meadows said he surveyed his members on Monday night, and though he wouldn’t give the tally, said it was fair to assume there were more than the 22 votes needed to block its passage.

“There are core things within this bill as it currently stands that would violate some of the principles of the Freedom Caucus,” he said.

Asked if his roughly three dozen members were prepared to vote the bill down during a House vote, Meadows said he was hopeful that “cooler heads will prevail” and the party would arrive at a solution that appeases both moderates and conservatives.

Still, the group has opted against taking a formal position on the legislation, allowing House leadership and White House officials to pressure individual members of the caucus to support the bill. Earlier on Monday, Meadows conceded that this was already happening.

“They’re already whipping with a whip that’s about 10 feet long and five feet wide,” he told reporters.

Leaving the meeting, Alabama representative Mo Brooks, a conservative member of the Freedom Caucus, said he didn’t see how the bill could pass unless Republican leaders managed to bring Democrats on board.

“I believe this is a really bad bill for the United States of America,” he said. “And I think we’re going to kill it.”